2,249 results match your criteria Microscopic Polyangiitis


Neutrophil activation in patients with anti-neutrophil cytoplasmic autoantibody-associated vasculitis and large-vessel vasculitis.

Arthritis Res Ther 2022 Jun 29;24(1):160. Epub 2022 Jun 29.

Division of Rheumatology, Department of Medicine, University of Washington, 750 Republican Street, Seattle, WA, 98109, USA.

Objective: To assess markers of neutrophil activation such as calprotectin and N-formyl methionine (fMET) in anti-neutrophil cytoplasmic autoantibody-associated vasculitis (AAV) and large-vessel vasculitis (LVV).

Methods: Levels of fMET, and calprotectin, were measured in the plasma of healthy controls (n=30) and patients with AAV (granulomatosis with polyangiitis (GPA, n=123), microscopic polyangiitis (MPA, n=61)), and LVV (Takayasu's arteritis (TAK, n=58), giant cell arteritis (GCA, n=68)), at times of remission or flare. Disease activity was assessed by physician global assessment. Read More

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Rituximab pediatric drug development: Pharmacokinetic and pharmacodynamic modeling to inform regulatory approval for rituximab treatment in patients with granulomatosis with polyangiitis or microscopic polyangiitis.

Clin Transl Sci 2022 Jun 28. Epub 2022 Jun 28.

JJG Pharma Consulting, Basel, Switzerland.

Anti-neutrophil cytoplasmic antibody-associated vasculitides granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) are rare, potentially organ- and life-threatening autoimmune conditions affecting adult and pediatric patients. An open-label phase II study was conducted to determine safe and effective dosing regimens of rituximab in pediatric patients with GPA/MPA. To determine the selection of an appropriate dose regimen in children for induction and maintenance, a population pharmacokinetic approach was used (nonlinear mixed-effect modeling), combining pediatric data with data from adults with GPA/MPA. Read More

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A Case of Proximal Posterior Inferior Cerebellar Artery (PICA) Aneurysm Treated with PICA-to-PICA Bypass and Trapping Surgery: Comparison with Occipital Artery-PICA Bypass.

NMC Case Rep J 2022 31;9:129-133. Epub 2022 May 31.

Department of Neurosurgery, Japan Community Health Care Organization Chukyo Hospital, Nagoya, Aichi, Japan.

Posterior inferior cerebellar artery (PICA) aneurysms often require cerebral vascular reconstruction for surgical treatment because of their characteristic morphology. Despite its potential complications, the occipital artery-to-posterior inferior cerebellar artery (OA-PICA) bypass is a typical treatment because of its versatility. Although a few cases of intracranial-to-intracranial bypass have been reported, this type of vascular reconstruction is only regarded as an alternative to the OA-PICA bypass because of the uncertainty of bypass feasibility and potential risk of ischemic complications. Read More

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MPO-ANCA-positive conversion and microscopic polyangiitis development in idiopathic interstitial pneumonia: a case report.

CEN Case Rep 2022 Jun 24. Epub 2022 Jun 24.

Division of Nephrology and Endocrinology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, 1-15-1 Fukumuro, Miyagino-ku, Miyagi, Sendai, 983-8536, Japan.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a systemic autoimmune disease characterized by necrotizing inflammation of the small blood vessels. ANCA-associated vasculitis is subclassified into three variants: granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, and microscopic polyangiitis (MPA). Myeloperoxidase (MPO) ANCA is a marker antibody for MPA. Read More

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Diagnostic and Therapeutic Approach in ANCA-Associated Glomerulonephritis: A Review on Management Strategies.

Front Med (Lausanne) 2022 3;9:884188. Epub 2022 Jun 3.

Department of Internal Medicine and Oncology, Semmelweis University, Budapest, Hungary.

Anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis is a destructive small vessel vasculitis affecting multiple organs. Renal involvement often leads to end-stage renal disease and increases mortality. Prompt diagnosis and initiation of adequate immunosuppressive therapy are critical for the best patient and kidney outcomes. Read More

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Polyarteritis nodosa: an evolving primary systemic vasculitis.

Postgrad Med 2022 Jun 22:1-8. Epub 2022 Jun 22.

Department of Medicine, Division of Rheumatology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.

Polyarteritis nodosa (PAN) is a primary form of vasculitis characterized by inflammation of primarily medium-sized arteries. Several key events have shaped the current spectrum of the disease including the separation of a subgroup with microscopic polyangiitis, the discovery of the association of hepatitis B, and the discovery of adenosine deaminase 2 deficiency (DADA2). With the discovery of secondary causes of PAN and changing nomenclature, the incidence of PAN has declined over time. Read More

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Early ultrastructural lesions of anti-neutrophil cytoplasmic antibody- versus complement-associated vasculitis.

Neuropathology 2022 Jun 15. Epub 2022 Jun 15.

Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan.

This study aims to describe electron microscopic findings of vasculitis associated with anti-neutrophil cytoplasmic antibody (ANCA) and complement. Sural nerve biopsy specimens were obtained from 10 patients with microscopic polyangiitis (MPA), a representative ANCA-associated vasculitis, and six patients with nonsystemic vasculitic neuropathy (NSVN), who were negative for ANCA but positive for complement deposition. In patients with MPA, attachment of neutrophils to epineurial vascular endothelial cells, migration of neutrophils to the extravascular space via the penetration of the endothelial layer, and release of neutrophil components to the extracellular space were observed. Read More

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A Novel Antineutrophil Extracellular Trap Antibody Targeting Myosin Light Chain 6 in Microscopic Polyangiitis.

J Rheumatol 2022 Jun 15. Epub 2022 Jun 15.

Department of Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University; Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University; Department of Pathology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan. This study was supported by grants from the Ministry of Health, Labour and Welfare of Japan for the Japan Research Committee for Intractable Vasculitis ( JPVAS; 20FC1044) and the Japan Agency for Medical Research and Development (ek0109360h0003). The authors declare no conflicts of interest relevant to this article. Address correspondence to Dr. A. Ishizu, Department of Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Kita-12, Nishi-5, Kita-ku, Sapporo 0600812, Japan. Email: hokudai.ac.jp.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is characterized by ANCA production in the serum. This disease entity includes microscopic polyangiitis (MPA). Previous studies have revealed that neutrophils excessively activated by ANCA and other serum factors are critically involved in AAV pathogenesis. Read More

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Relapsing subarachnoid hemorrhage as a clinical manifestation in microscopic polyangiitis: a case report and literature review.

Clin Rheumatol 2022 Jun 11. Epub 2022 Jun 11.

Department of Rheumatology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200001, China.

Microscopic polyangiitis (MPA) is a systemic small-vessel vasculitis associated with anti-neutrophil cytoplasmic antibody (ANCA) and predominantly causes kidney and pulmonary injuries. Subarachnoid hemorrhage, a life-threatening manifestation of the central nervous system (CNS), rarely occurs in patients with ANCA-associated vasculitis (AAV). We report the case of a young man with spontaneous SAH recurrence and active nephritis. Read More

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A case of cardiac calcified amorphous tumor complicated with acute myocardial infarction.

J Cardiol Cases 2022 Jun 31;25(6):396-399. Epub 2022 Jan 31.

Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan.

An 80-year-old woman with a history of eosinophilic granulomatosis with polyangiitis, cardiac hypertrophy, and diabetes called for an ambulance after developing chest pain. She was diagnosed with acute myocardial infarction (AMI), and coronary angiography revealed occlusion of the right coronary artery. Coronary aspiration was performed, and coronary aspirate was white with calcified factor. Read More

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Incidence and Patterns of Interstitial Lung Disease and Their Clinical Impact on Mortality in Patients with Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: Korean Single-Centre Observational Study.

J Immunol Res 2022 23;2022:2499404. Epub 2022 May 23.

Division of Rheumatology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.

Objectives: This study investigated the frequency and patterns of interstitial lung disease (ILD) and their clinical effect on all-cause mortality during the follow-up period in patients with antineutrophil cytoplasmic antibody- (ANCA-) associated vasculitis (AAV) in Korea.

Methods: The medical records of 255 AAV patients with ILD were retrospectively reviewed. ILD and its patterns, the usual interstitial pneumonia (UIP) and non-UIP patterns, were confirmed using high-resolution computed tomography both at AAV diagnosis and during follow-up. Read More

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A Case of Muscle Biopsy-proven Drug-induced Microscopic Polyangiitis in a Patient with Tuberculosis.

Intern Med 2022 May 31. Epub 2022 May 31.

Department of Infection Control Science, Graduate School of Medicine, Osaka City University, Japan.

We herein report a case of muscle biopsy-proven microscopic polyangiitis (MPA) in a patient with tuberculosis. The patient had developed a persistent fever after the initiation of treatment for tuberculosis and was positive for myeloperoxidase-antineutrophil cytoplasmic antibody (ANCA). However, because conventional symptoms were lacking, determination of the biopsy site was difficult. Read More

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Eosinophilic Granulomatosis With Polyangiitis Presenting With Oral Granuloma as the Initial Symptom: A Case Report.

Front Med (Lausanne) 2022 10;9:842137. Epub 2022 May 10.

Department of Nephrology, The Third Affiliated Hospital of Chongqing Medical University (General Hospital), Chongqing, China.

Antineutrophil cytoplasmic antibody associated vasculitis includes granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis (EGPA), and microscopic polyangiitis. While EGPA has no specific symptoms, it usually presents as necrotizing vasculitis, eosinophil infiltration of the tissues and organs, and extravascular granuloma formation. Here, we report a patient who had a rare initial presentation of oral granuloma and had been previously misdiagnosed several times at other hospitals. Read More

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Application of the 2022 ACR/EULAR criteria for microscopic polyangiitis to patients with previously diagnosed microscopic polyangiitis.

Clin Exp Rheumatol 2022 May 19. Epub 2022 May 19.

Division of Rheumatology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, and Institute for Immunology and Immunological Diseases, Yonsei University College of Medicine, Seoul, Republic of Korea.

Objectives: This study applied the 2022 American College of Rheumatology/European Alliance of Associations for Rheumatology (the 2022 ACR/EULAR) criteria for microscopic polyangiitis (MPA) to patients with previously diagnosed MPA as per the 2007 European Medicines Agency algorithm (the 2007 EMA algorithm) and the 2012 revised International Chapel Hill Consensus Conference nomenclature of vasculitides (the 2012 CHCC definitions) The concordance rate between the new and old criteria was investigated.

Methods: This study included 117 patients with MPA, and the new criteria were applied to these patients. MPA could be classified when the total score is ≥5. Read More

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Antineutrophil Cytoplasmic Antibody-Associated Vasculitis and COVID-19: The Clinical Course and Prognosis of 15 Patients From a Tertiary Care Center.

J Clin Rheumatol 2022 May 25. Epub 2022 May 25.

From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine.

Objective: The aim of this study was to evaluate incidence rates, prognoses, and disease-related factors associated with poor outcomes in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV) who had coronavirus disease (COVID-19).

Methods: Patients with AAV were questioned for a history of COVID-19 in the outpatient setting. Cumulative clinical findings and treatment history were obtained from the patients' medical records. Read More

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Remission and Low-Disease Activity in Granulomatosis with Polyangiitis and Microscopic Polyangiitis: Prevalence and Impact on Damage Accrual.

Arthritis Care Res (Hoboken) 2022 May 23. Epub 2022 May 23.

Service de Médecine Interne, Centre de Référence Maladies Autoimmunes Systémiques Rares d'Ile de France, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France.

Objectives: To assess the prevalence and impact on damage accrual of different levels of disease activity in patients with granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA).

Methods: Patients with GPA and MPA followed for ≥5 years in two different centers were included. Disease activity and damage were assessed using Birmingham Vasculitis Activity Score (BVAS) and Vasculitis Damage Index (VDI), respectively. Read More

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Cutaneous manifestations of antineutrophil cytoplasmic antibody-associated vasculitis (AAV): a concise review with emphasis on clinical and histopathologic correlation.

Int J Dermatol 2022 May 22. Epub 2022 May 22.

Departments of Dermatology and Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) comprises a group of small vessel vasculitides grouped by commonalities of clinical manifestations and ANCA testing. Skin findings are not uncommon, although there is considerable overlap and many times nonspecificity. In general, patients with skin findings tend to have more significant systemic illness, and skin lesions most often develop simultaneously or following onset of systemic symptoms. Read More

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Validation of anti-neutrophil cytoplasm antibodies associated vasculitides diagnosis codes from the electronic health records of two French university hospitals.

Eur J Intern Med 2022 May 18. Epub 2022 May 18.

Service de Médecine Interne, Centre de Référence des maladies auto-immunes systémiques rares d'Ile de France, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France; Université de Paris, F-75006 Paris, France. Electronic address:

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Analysis of Various Types of Glomerulonephritis with Crescents at a Single Center.

Int J Nephrol 2022 9;2022:1749548. Epub 2022 May 9.

Department of Nephrology, Tokyo Women's Medical University, Tokyo, Japan.

Background: The importance of crescent formation in glomerulonephritis has increased. However, detailed analysis of crescentic glomerulonephritis in Asia is scarce. In addition, advances in serological diagnostic techniques (antineutrophil cytoplasmic and antiglomerular basement membrane autoantibodies) and early diagnosis have reduced the number of cases meeting the strict definition of crescentic glomerulonephritis (>50% of glomeruli are crescentic). Read More

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[ANCA-Associated Vasculitides].

Ther Umsch 2022 Jun;79(5):229-237

Klinik für Rheumatologie, Universitätsspital Basel.

ANCA-Associated Vasculitides The according to their immunoserological markers (anti-neutrophil cytoplasmic antibodies - ANCA) named ANCA-associated vasculitides (AAV) are classified following the Chapel Hill nomenclature (2012). Microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic granulomatosis with polyangiitis (EGPA) are categorized according to clinical, histological, and imaging findings. GPA and EGPA mainly differ from MPA in the presence of granulomatous inflammation within the airways. Read More

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Microscopic Polyangiitis Following mRNA COVID-19 Vaccination: A Case Report.

J Korean Med Sci 2022 May 16;37(19):e154. Epub 2022 May 16.

Department of Internal Medicine, Hanyang University Guri Hospital, Guri, Korea.

Coronavirus disease 2019 (COVID-19) is one of the most widespread viral infections in human history. As a breakthrough against infection, vaccines have been developed to achieve herd immunity. Here, we report the first case of microscopic polyangiitis (MPA) following BNT162b2 vaccination in Korea. Read More

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Added value of Joint ENT-Rheumatology clinic in the management of ANCA-associated vasculitis: One year's experience.

Am J Otolaryngol 2022 Jul-Aug;43(4):103485. Epub 2022 May 5.

ENT Department, Sheffield Teaching Hospitals NHS Trust, Sheffield, UK.

Purpose: ANCA-associated vasculitides (AAV) represent a group of diagnoses, including granulomatosis with polyangiitis (GPA), eosinophilic granulomatosis with polyangiitis (EGPA) and microscopic polyangiitis (MPA). Most commonly, they present initially with ENT-associated symptomatology, and therefore they often pose a diagnostic challenge. We aim to present our one-year experience in the joint management of AAV in a multi-disciplinary setting. Read More

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Systematic Review and Metaanalysis of Worldwide Incidence and Prevalence of Antineutrophil Cytoplasmic Antibody (ANCA) Associated Vasculitis.

J Clin Med 2022 May 4;11(9). Epub 2022 May 4.

Instituto de Investigación Biomédica de Málaga (IBIMA), UGC de Reumatología, Hospital Regional Universitario de Málaga, 29010 Malaga, Spain.

Objective: In this study, we aimed to evaluate the worldwide incidence and prevalence of ANCA-associated vasculitis (AAV).

Methods: A systematic search of Medline and Embase was conducted until June 2020 for studies that analyzed the incidence and prevalence of patients aged >16 years diagnosed with AAV in different geographical areas. A meta-analysis was undertaken to estimate the pooled incidence per million person-years and prevalence per million persons in AAV overall and for each subtype of AAV: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Read More

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A past medical history of autoimmune disease predicts a future with fewer relapses in patients with ANCA-associated vasculitis.

Clin Exp Rheumatol 2022 May 4;40(4):741-750. Epub 2022 May 4.

Department of Nephrology and Transplantation Unit, Laiko Hospital, National and Kapodistrian University of Athens, Greece.

Objectives: To explore the frequency and impact of an autoimmune disease past-medical history (PMH) in the clinical picture and outcomes of patients with antineutrophil cytoplasmic autoantibodies (ANCA) associated vasculitis (AAV).

Methods: This was a retrospective study of patients with biopsy-proven AAV, >16 years old, with detailed information about their PMH. Outcomes of interest included remission, treatment resistance, relapse, end-stage kidney disease (ESKD), and death. Read More

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Rituximab treatment in ANCA-associated vasculitis patients: outcomes of a real-life experience from an observational cohort.

Clin Rheumatol 2022 May 4. Epub 2022 May 4.

Department of Immunology and Rheumatology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Vasco de Quiroga No. 15, Colonia Sección XVI, Tlalpan, 14080, Mexico City, Mexico.

Rituximab is a first-line therapy in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Among previous studies evaluating its efficacy, the Hispanic/Latino population has been underrepresented. This study aimed to assess the outcomes of AAV patients treated with rituximab in a tertiary care center in Mexico. Read More

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[Pediatric ANCA-associated vasculitis, a case series].

Andes Pediatr 2021 Dec 8;92(6):904-910. Epub 2021 Sep 8.

Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.

Introduction: ANCA-associated vasculitis (AAV) is an infrequent disease in childhood. International literature about pediatric vasculitis is scarce, and it mainly refers to other systemic vasculitides with a higher incidence in childhood, such as IgA vasculitis and Kawasaki disease.

Objective: To describe the clini cal and laboratory characteristics of a series of pediatric cases with AAV. Read More

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December 2021

Association of M2 Macrophages, Th2, and B Cells With Pathomechanism in Microscopic Polyangiitis Complicated by Interstitial Lung Disease.

J Rheumatol 2022 May 2. Epub 2022 May 2.

S. Matsuda, MD, PhD, T. Kotani, MD, PhD, T. Suzuka, MD, PhD, T. Kiboshi, MD, Y. Wada, MD, PhD, T. Ishida, MD, PhD, H. Shiba, MD, K. Hata, MD, T. Shoda, MD, T. Takeuchi, MD, PhD, Department of Internal Medicine (IV), Osaka Medical and Pharmaceutical University, Takatsuki; H. Kuwabara, MD, PhD, Y. Hirose, MD, PhD, Department of Pathology, Osaka Medical and Pharmaceutical University, Takatsuki; Y. Fujiki, MD, PhD, Department of Rheumatology, Yodogawa Christian Hospital, Osaka, Japan. The authors declare no conflicts of interest relevant to this article. Address correspondence to Dr. T. Kotani, MD, PhD, Department of Internal Medicine (IV), Osaka Medical and Pharmaceutical University, Daigaku-Machi 2-7, Takatsuki, Osaka 569-8686, Japan. Email: Accepted for publication April 20, 2022.

Objective: To address the pathomechanism of microscopic polyangiitis (MPA) complicated by interstitial lung disease (ILD) using serum biomarker profile and pulmonary histopathology.

Methods: Serum biomarkers from patients with MPA-ILD (n = 32), MPA without ILD (n = 17), and healthy controls (n = 10) were examined. Based on the biomarker profiles, principal component analysis (PCA) and cluster analysis were performed to classify patients with MPA-ILD into subgroups. Read More

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Cutaneous manifestations of acute kidney injury.

Clin Kidney J 2022 May 9;15(5):855-864. Epub 2021 Dec 9.

Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Central Parkway, Newcastle upon Tyne, UK.

Acute kidney injury (AKI) is a common medical problem with a multitude of aetiologies. Prompt diagnosis and management is key in the prevention of complications. Cutaneous signs can often give diagnostic clues of underlying systemic diseases causing AKI. Read More

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Disease Severity and Response to Induction Therapy in Hispanic Patients With Antineutrophilic Cytoplasmic Autoantibody-Associated Vasculitis-Related Diffuse Alveolar Hemorrhage.

Cureus 2022 Apr 25;14(4):e24470. Epub 2022 Apr 25.

Internal Medicine, University of Texas Rio Grande Valley School of Medicine, Edinburg, USA.

Objectives We examined the response to induction therapy of Hispanic patients with antibody-associated vasculitis (AAV)-related diffuse alveolar hemorrhage (DAH). This study aimed to determine the severity of disease at presentation and the response to induction therapy in our patient population. Methods We retrospectively reviewed the clinical data of Hispanic patients hospitalized with antineutrophil cytoplasmic antibody (ANCA) vasculitis between October 1, 2010, and December 31, 2021. Read More

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Clinical and Renal Histology Findings and Different Responses to Induction Treatment Affecting the Long-Term Renal Outcomes of Children With ANCA-Associated Vasculitis: a Single-Center Cohort Analysis.

Front Immunol 2022 14;13:857813. Epub 2022 Apr 14.

Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Introduction: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is relatively rare in children. This article aimed to analyze clinical and renal histology findings and different responses to induction treatment associated with the long-term renal outcomes in children with AAV in a single center.

Methods: All pediatric patients with AAV admitted to Tongji Hospital from January 2002 to January 2021 were included in the study. Read More

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